*Note: ACL is a human anatomical term, while CrCL (Crenial Cruciate Ligament) is the dog equivalent. In this article I will use the terms interchangeably
medial & lateral collateral, the ACL which is the anterior or crenial cruciate ligament (CrCL/ACL), and caudal/posterior cruciate.The function of the ACL is threefold: the first and most significant function is to prevent the forward thrust of the tibia. Second, the ACL limits internal rotation of the tibia. And finally the Anterior Cruciate Ligament prevents hyperextension of the knee joint (stifle).
Your bulldog puppy (or any other breed of dog) was born with a knee that has a slight degree of flexion. This is normal for a dog, but abnormal for a human. Because of this anatomical bending, and natural sloped knee, your bulldog puppy ACL is always load-bearing, meaning it always has tension on it. To demonstrate the knee biomechanics, think of two parked cars, one facing uphill with the brake cable (“the car ACL”) stretched to the limit as it holds against the downhill roll. This model represents your french bulldog puppy knee in its natural state. The second car is parked on a flat road with the brake cable under no tension (i.e. the “car ACL ” has hardly any daily wear and tear), representing a normal healthy human knee. Because dog’s tibial plateau is naturally sloped, there is a force created that transmits a forward motion to the tibia. This force is called ‘Cranial Tibial Thrust’ , (better known as “draw” )and is one in which the anterior cruciate ligament is countering by preventing this natural forward motion of the tibia and backward motion of the femur.
When your english bulldog puppy ACL tears, any weight-bearing movement causes your bulldog femur bone to slide down this slope, rubbing the tibia, which inflicts pain. Often, compounding that pain is the meniscal cartilage —a cushion between the two bones that acts as a shock absorber—being crushed by the sliding femoral bone. Once again, imagine your car facing uphill but this time, add a safety wooden block (mensci) behind the back wheel. Now, imagine that the cable-brake (“your bulldog puppy ACL”) suddenly snaps, placing all the car’s weight and downhill roll on that safety wooden block (“your bulldog puppy mensci”). You can see why 50% of dogs with ACL injuries, will present with an injured meniscal cartilage. Meniscal tear is often accompanied by a “click” that can be heard when your french bulldog or american bulldog walks. That is why most bulldog puppies with a torn ACL will not put any weight on the leg, or if they do, they will just toe touch the leg to the ground While canine and human knee anatomies are very similar, our biomechanics differ greatly. Start by looking at the differences in posture: we stand heels on the ground and our knees are essentially straight during weight bearing. Contrast that with your bulldog, who stand hocks/ankle elevated, with their knees bent during weight bearing. The significance of this difference is that there are different force vectors in the canine knee than in the human knee. In a normal canine knee this shearing force is counteracted by the large muscles of the leg, notably the quadriceps group and hamstrings. However, in situations where the leg muscles are unable to resist this shear, all that is left as the last line of defense, Mother Nature’s “emergency brake” if you will, is the ACL. Humans have a relatively level tibial plateau: about a four-degree (4) tibial plateau angle (TPA) and tears are usually due to an acute athletic injury, whereas bulldogs have an average TPA’s of 25 to 30, therefore tears are typically due to chronic biomechanical stress caused by the downward sloping of the tibial plateau, as I explained above. It is why bulldogs and bulldog puppies with untreated ACL tears usually do poorly in comparison with humans.
The goal of ACL surgery is to stabilize the knee joint and thus minimize DJD ( Degenerative Joint Disease, canine Osteoarthritis, Bulldog Arthritis,) progression, as well as management of meniscal injury. A variety of repair methods have been used and they can be divided into static repairs, which attempt to replace the function of your bulldog CrCL (ACL), and dynamic repairs, which alter the knee biomechanics to absolve the need for a functioning CrCL. Static repairs include intracapsular grafting techniques,
extracapsular lateral suture techniques, tight rope, and fibular head advancement. Dynamic repairs involve neutralization of cranial tibial thrust (or cranial drawer) as the primary goal. The two current dynamic repair techniques addressing the underlying biomechanical instability in a canine ACL tear are the tibial plateau leveling osteotomy (TPLO) and the tibial tuberosity advancement (TTA). The TPLO which changes the angle of the tibial plateau has been popular for over a decade and is considered the gold standart for bulldogs and other medium and large breed dogs. The TTA is a technique that changes the relationship of the patellar tendon and tibial plateau angle via an osteotomy (bone cut).
Keep your bulldog puppy in shape, keep him/her toned and keep him/her lean. It is not hard to imagine that less active bulldogs will have disuse atrophy, thus poorer muscle function critical to help and “protect” the ACL. Bulldog obesity also increases the weight load on the knee, thus intensifying the ACL daily wear and tear. In addition to weight control I recommend you keep your bulldog puppies on a joint supplement like Dr. Kraemer’s V4B Bulldog Total Joint for Advanced Osteoarthritis or V4B Bulldog Joint Protector for early stage joint disease. Fish oils (omega 3) like Dr. Kraemer’s V4B Bulldog Fish Oil Skin & Joint are also beneficial.
When the Anterior Cruciate Ligament tear surgical repair must be done by a skilled, experienced surgeon, nevertheless 90% of a successful outcome depends on owner compliance. When it comes to choosing TPLO vs. TTA, many of you are confused. First, you should know that not just any veterinarian can perform either of these procedures. In order to truly master these surgical techniques, extensive training is required. Second, within the veterinary profession, even to date, there is still constant debate which surgical procedure is the best overall. One veterinary surgeon may say one thing and another may have a completely different opinion. Naturally, when a surgeon is heavily invested in one technique, he or she is likely to favor it over the other, thus in his or her mind it is the “superior method” despite the obvious bias. In general, all things being equal, in the right hands, they are both excellent surgical choice. The surgeon’s skill and experience in executing their chosen technique to perfection is what count is the most.
Dr. Kraemer’s Bulldog ACL Tear Tip #1: In my hospital “Vet4HealthyPet Advanced Medical Cae” we now offer a new, revolutionary, regenerative medicine, state of the art technology called stem cell therapy. Many of our orthopedic patients opt to add stem cell therapy to the surgical and treatment plan. When combined with surgery the cost is dramatically reduced. In addition other joints and medical condition can be treated simultaneously. Last, as an additional benefit we almost always also cryobank some of pet stem cells for future medical and surgical needs.
I am often asked if stem cell therapy it is a good noninvasive alternative to ACL tear surgery repair. In general, my answer is “NO” because the treatment does not fix the biomechanical problems. Nevertheless on many occasions I recommended and performed stem cell therapy in combination with surgery to improve healing, range of motion and osteoarthritis, as well as to try and save the opposite side from tearing (it is my experience that about 50% of bully’s will have the other knee torn within one year.). In addition, we almost always also cryobank some of our client pet’s stem cells for future medical and surgical needs. Last, most of the better pet insurance companies now cover stem cell therapy for pets.
There are exceptions to the rule, and on special occasions I have treated dogs with ACL tears non-surgically with stem cell therapy alone. Sometimes owners refuse surgery due to the dog advanced age, the risk of prolonged anesthesia, cost, the long post-op confinement, and the long road to recovery (3-4 months). Other cases were we will consider substituting stem cell therapy for surgery is for dogs suffering from multiple orthopedic problems in addition to the ACL tear, such as elbow dyspepsia, bad hip, bad arthritic hocks (Tarsal or Ankle Joint, etc.), especially in mid-age and older dogs. In those cases surgical repair of only one problem might not make sense. In contrast, Stem Cell Therapy can provide pain relief for multiple injuries at once, with minimal anesthesia and minimal post-surgery down time all at relatively low cost. Plus the stem cells can be cyrobanked for additional future treatments
Dr. Kraemer’s Bulldog ACL Tear Tip #2: Most of my pets, dog and cats, orthopedic surgical cases also receive PRP (Platelet Rich Plasma) as a direct injection to their joins. The cost is minimal and the benefits are widely known both (for pets and humans) when it is done in conjunction with a surgical procedure.
Dr. Kraemer’s Bulldog ACL Tear Tip #3: Pain and lameness with ACL injury to your bulldog is due to instability of the stifle joint and inflammationion. The stretching of the joint capsule, which in time initiates a cascade of events, including cartilage degradation, and degenerative joint disease which all contribute to the pain and lameness.
Dr. Kraemer’s Bulldog ACL Tear Tip #4: Often your bulldog pain is exacerbated when the medial meniscus become crushed under the medial femoral condyle, as the tibia is drawn forward and the femur slide backward during cranial tibial thrust.
Dr. Kraemer’s Bulldog ACL TearTip #5: Bulldogs and other dogs with a CrCL injury and a subtle lameness may exhibit a shortened stride and a somewhat extended stifle. The normal limb will appear to land harder on the ground. Pay attention to how the dog sits. The dog may sit with the leg extended and out to the side. This is known as the “positive sit test”.
Dr. Kraemer’s Bulldog ACL Tear Tip #6: In addition to the forward thrust, your bulldog ACL also prevents inner rotation of the tibia which might be the reason why ACL tears are so common in bulldogs and bulldog puppies. Bulldogs have an excessive weight load resting on the inner part of the tibia due to the their unusual anatomy /physique manifested by a relatively heavy weight and large body, in contrast to their short axial bones and broad angulated stance.
Dr. Kraemer’s Bulldog ACL Tear Tip #7: Almost all bulldogs have some degree of hip dyspepsia and many also suffer from Medial Patella Luxation. Those two orthopedic conditions will affect your bulldog quadriceps, gastoric (calf) and hamstrings muscles, shorting and contracting them, which further contribute to that inner tibial load.
Dr. Kraemer’s Bulldog ACL Tear Tip #8: It is my conclusion that bulldog’s knee’s tibial femoral space is different than other breeds. This finding has been confirmed with my orthopedic surgeon, Dr. Paul Cechner, Diplomate A.C.V.S. who has been operating on dog’s knees for over 40 years and on my bulldog patients knees for a decade. We observed s a narrowing in bulldogs of the tibial femoral space in the inner part of the joint at the ACL attachment, which leaves very little wiggle room for the ligament and might add additional wear and tear and the greater possibility for rupture or partial tears.
Dr. Kraemer’s Bulldog ACL Tear Tip #9: : Sometimes you will be able to feel a bump (“medial buttress”) on the inner aspect of your French Bulldog puppy knee, which is a fibrotic response to stifle instability.
Dr. Kraemer’s Bulldog ACL Tear Tip #9: Radiographs are very helpful in diagnosing of bulldogs ACL tears and rupture. In some instances the radiograph will actually catch the joint in this slipped/draw position. Other common radiographic findings are joint effusion (fluid) and evidence of osteoarthritis.
Dr. Kraemer’s Bulldog ACL Tear Tip #10: In my practice the most common presentation of an ACL injury is a dog that has a history of acute onset hind limb lameness with improvement usually with pain management medication and rest, followed by recent worsening of the lameness. These dogs may have had a partial tear that improved with rest, and then went on to re-injure or fully rupture.
Dr. Kraemer’s Bulldog ACL Tear Tip #11: Most bulldogs ACL rapture or partial ruptures are painful when the tibial thrust maneuver is preformed and/or the stifle is placed in hyperextension.
Dr. Kraemer’s Bulldog ACL Tear Tip #12: I rarely recommend static repairs (typically done in human patients) which attempt to replace the function of the ACL but fail to address the biomechanical problems. TPLO repair (Tibial Plato Leveling Osteotomy) is our preferred surgical repair method. The philosophy behind TPLO surgery is to completely change the dynamics of the dog’s knee so that the torn ligament becomes irrelevant to the knee stability. The TPLO completely alters the dynamics of the knee by neutralizing the effect of the forward tibial thrust. Once the tibia is cut and rotated the femur can no longer slide backwards and the knee is immediately stabilized. Menisci injuries in bulldogs are also corrected during the surgery eliminating pain and preventing further arthritic changes to the joint.
Dr. Kraemer’s Bulldog ACL TearTip #13: When choosing between TPLO and TTA the breed, degree of tibial sloop, tibial plateau, the health of the patella and patella ligament, the dog’s general anatomy, degree of osteoarthritis, and age, should all be taken into account. But most importantly is the surgeon’s experience with the elected procedure.
Dr. Kraemer’s Bulldog ACL Tear Tip #14: The cost of TPLO surgery in dogs varies depending on region and who is performing the surgery.
Dr. Kraemer’s Bulldog ACL Tear Tip#15: A bulldog puppy suffering from an ACL injury might have just a subtle limp often manifested by a slowly worsening lameness with a sudden acute onset non-weight bearing lameness. However, unlike humans the injury is rarely of purely traumatic etiology.
Dr. Kraemer’s Bulldog ACL Tear Tip #16: Partial ACL rupture in bulldogs puppies is not uncommon. In some cases a complete tear of only one portion of the ligament may occur. Due to the degenerative nature of most ACL ruptures, a significant proportion of bulldogs will proceed to a full tear.
Dr. Kraemer’s Bulldog ACL Tear Tip #17: All our Anterior Cruciate (ACL) surgeries (TPLO, Tight Rope, Extra Capsule) and other orthopedic surgeries are treated post op with class 4 cold laser therpyto reduce pain and enhance healing.
Dr. Kraemer’s Bulldog ACL Tear Tip #18: All our ACL surgeries (TPLO, Tight Rope, Extra Capsule) and other orthopedic surgeries are sent home post op with main management medication (NASID and other Analgesics). In many cases we also send our post op surgical cases and TPLO ACL repairs with PEMT loop, a non pharmacological battery operated safe device that enhance healing, reduced inflammation and improve pain control.
Dr. Kraemer’s Bulldog ACL Tear Warning #1: When left untreated, ACL injuries in dogs almost always lead to progressive osteoarthritis, a lifelong, debilitating, chronic painful condition. Frequently, untreated ACL injuries will also lead to uneven weight bearing, forcing overcompensation of other legs and joints, the contra lateral knee being the most likely, thus increasing the chances of additional injuries and ACL tears.
Dr. Kraemer’s Bulldog ACL Tear Warning #2: Canine stifle anatomy and biomechanics differ from humans and lack of this understanding has resulted in many misconceptions by the pet owning public. Non-surgical treatments are usually unsuccessful in bulldogs ACL tears due to the chronic biomechanical stress, your bulldog puppy tibial plateau slope and joint biomechanics is why braces are relatively ineffective.
Dr. Kraemer’s Bulldog ACL Tear Warning #3: The bulldog puppy tibial slope and resulting sliding action are why most orthopedic veterinary surgeons have abandoned old style static replacement procedures in favor of the dynamic ones like TPLO and TTA. Again, this is in sharp contrast to human orthopedics where replacement with a biological graft is the standard.
Dr. Kraemer’s Bulldog ACL Tear Warning #4: Bulldog CrCL injury should be suspected and ruled out in any case of hind-limb lameness. Affected dogs may have a variety of presentations, probably due to the multifactorial nature of the disease. Your bulldog puppy may be non-weight bearing, partially-weight bearing, or occasionally non-ambulatory.
Dr. Kraemer’s Bulldog ACL Tear Warning #5: Some dogs present with a mild, chronic lameness and may have only a partial CrCL rupture, with minimal effusion and no osteoarthritis visible on radiographs. These dogs may have no cranial drawer sign, but will exhibit discomfort when tibial trust maneuver is preformed and/or pain due to the crashing of the inner manisci when the stifle is placed in hyperextension.
Dr. Kraemer’s Bulldog ACL Tear Warning #6: Less commonly, some bulldogs may present acutely non-ambulatory, or with difficulty rising, or with shifting leg lameness. They are often diagnosed erroneously as a neurological case (disc disease, spina bifida, etc) . To make things more challenging, these patients sometimes have concurrent hip dysplasia, DJD and lumbosacral disease. Even with concurrent diseases, a good orthopedic exam can evaluate CrCL status with confidence.
Dr. Kraemer’s Bulldog ACL Tear Warning # 7: both your French Bulldog legs should be examined and radiographed. Very often the opposite side is also injured due to overcompensation. I usually start with the “good” leg to allow your bully to relax and get an idea of what baseline responses are. I begin by flexing and extending the joint to assess range of motion, crepitus, or clicking noise. Some may have diminished range of motion due to fibrosis, pain, or effusion. Crepitus can be consistent with degenerative joint disease (osteoarthritis). A palpable or audible click may indicate a meniscal tear.
Dr. Kraemer’s Bulldog ACL Tear Warning #8: If no drawer is palpated in your bulldog, but CrCL injury is still suspected, cranial drawer should be re-evaluated under sedation because they are resisting palpation with their leg muscles, or/and they have significant fibrosis which has stabilized the stifle. Lack of drawer sign in your bulldog knee can also be due to a partial ligament tear and the remaining intact ligament resisting gross displacement.
Dr. Kraemer’s Bulldog ACL Tear Warning #9: many bulldogs have MPL (medial/inner patella laxation) prior, or in addition to ACL injuries. These two conditions can be interwoven, since many patients with an MPL have medial rotation of the tibial crest, which puts continuous tension on the ACL. This is thought to predispose tearing of the ACL. In addition, chronic osteoarthritis, present in the stifles of bulldog puppies with MPL will initiate an enzymatic environment that can lead to degradation of the ACL. Last, rupture of the ACL tends to make the degree of patellar luxation worse, because a restraint on inward rotation of the tibia has been lost and because cranial displacement of the tibia during weight bearing moves the insertion of the patellar tendon, thus “lifting” the patella out of the trochlear groove and facilitating luxation.
Dr. Kraemer’s Bulldog ACL Tear Warning #10: Even in cases where a clear diagnosis of your bulldog CrCL rupture can be made in the exam room, radiographic examination of the joints and hips are indicated. Radiographs are used to rule out concurrent diseases and secondary signs of CrCL rupture, primarily joint effusion with fat pad displacement, and degenerative joint disease (DJD). The degree of DJD may be an indicator of prognosis, as dogs with minor degenerative changes probably have a better prognosis for long-term function than do those with advanced osteoarthritis. In cases without positive cranial drawer or trust, these give support to the diagnosis
Dr. Kraemer’s Bulldog ACL Tear Warning #11: Acute bilateral ACL ruptures (i.e. both ACL tear at once) are rare and can present a diagnostic challenge, since they may appear to be a neurological condition, such as degenerative myelopathy in dogs or herniation of an intervertebral disc. These dogs have great difficulty rising and may appear to have hind limb paresis.
Dr. Kraemer’s Bulldog ACL Tear Warning #12: I dont recomend treating bulldog ACL injuries with long term cortisone (prednisone) medication, due to the steroid effects on cartilage and healing as well as other adverse effects its known for.